package com.gds.utils;

import java.security.MessageDigest;

public class MD5Util {

    private static char hexDigits[] = {'0', '1', '2', '3', '4', '5', '6', '7', '8', '9',
            'a', 'b', 'c', 'd', 'e', 'f'};

    /**
     * md5加密
     *
     * @param message
     * @return
     */
    public static String digest(String message) {
        if (message == null || "".equals(message)) {
            return "";
        }
        try {
            byte[] strTemp = message.getBytes("UTF-8");
            MessageDigest mdTemp = MessageDigest.getInstance("MD5");
            mdTemp.update(strTemp);
            byte[] md = mdTemp.digest();
            int j = md.length;
            char str[] = new char[j * 2];
            int k = 0;
            for (int i = 0; i < j; i++) {
                byte byte0 = md[i];
                str[k++] = hexDigits[byte0 >>> 4 & 0xf];
                str[k++] = hexDigits[byte0 & 0xf];
            }
            return new String(str);
        } catch (Exception e) {
            return null;
        }
    }

    /**
     * md5加密
     *
     * @param message
     * @param isUpperCase
     * @return
     */
    public static String digest(String message, boolean isUpperCase) {
        return isUpperCase ? digest(message).toUpperCase() : digest(message);
    }
}
